#include<bits/stdc++.h>
using namespace std;
int max(int x,int y,int z){
  return max(x,max(y,z));
}
int min(int x,int y,int z){
  return min(x,min(y,z));
}
int mid(int x,int y,int z){
  if(x<y)swap(x,y);
  if(y<z)swap(y,z);
  if(x<y)swap(x,y);
  return y;
}
int f1(int a,int b,int c){
  return 100*max(a,b,c)+10*mid(a,b,c)+min(a,b,c);
}
int f2(int a,int b,int c){
  return 100*min(a,b,c)+mid(a,b,c)+max(a,b,c);
}
int main(){
	int num,cnt=0,a,b,c,ax,in;
	cin>>sun;
	while(num!=495){
		c=num%10;
		b=num/10%10;
		a=num/100;
        ax=f1(a,b,c);
        in=f2(a,b,c);
		num=ax-in;
		cnt++;
	}
	cout<<cnt;
	return 0;
}

谢谢大佬！

#include<bits/stdc++.h>
int maxof3(int a, int b, int c){
	int t;
	if (a < b){
		t = a;
		a = b;
		b = t;
	}
	if (a < c){
		t = a;
		a = c;
		c = t;
	}
	if (b < c){
		t = b;
		b = c;
		c = t;
	}
	return (a * 100 + b * 10 + c);
}
int minof3(int a, int b, int c){
	int t;
	if (a < b){
		t = a;
		a = b;
		b = t;
	}
	if (a < c){
		t = a;
		a = c;
		c = t;
	}
	if (b < c){
		t = b;
		b = c;
		c = t;
	}
	return (100 * c + 10 * b + a);
}
int main(){
	int num, cnt = 0;
	int a1, b1, c1;
	int max, min;
	scanf("%d", &num);
	while (num != 495){
		c1 = num % 10;
		b1 = num / 10 % 10;
		a1 = num / 100;
		max = maxof3(a1, b1, c1);
		min = minof3(a1, b1, c1);
		num = max - min;
		cnt++;
	}
	printf("%d", cnt);
	return 0;
}